#define  _CRT_SECURE_NO_WARNINGS  1
#include <stdio.h>
int main() {
    int a = 0;
    int b = 0;
    int c = 0;
    while (scanf("%d %d %d", &a, &b, &c) != EOF) {
        if ((a + b > c) && (a + c > b) && (b + c > a)) {
            if ((a == b) || (b == c) || (c == a)) {
                if (a == b && a == c)
                    printf("Equilateral triangle!\n");
                else
                    printf("Isosceles triangle!\n");
            }
            else
                printf("Ordinary triangle!\n");
        }
        else
            printf("Not a triangle!\n");

    }



    return 0;
}